JSFiddle - React, Tailwind, and code Playground

JavaScript

/*
= Description

Here is a very simple example on how the context has changed from < 1.8 to > 1.9. 
 
= To reproduce

1. Open the inspector and then hit the ”run” button.
2. Then select a newer version of jQuery from the drop-down.
3. Re-run the code. Observe and compare the two context object (”this”) printed in the console.
*/
var def = $.Deferred();
def._id = '123';
def.done(function(){
    console.log('def._id:', typeof this._id);
    console.log(this);
});
def.resolve();